POLYMORPHS

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the thermoanalysis of the anhydrous form A/B.

FIG. 2 shows a cyclic DSC diagram, in which the phase transition from −40° C. to 120° C. and vice versa has been run through a total of 3 times.

FIG. 3 shows an X-ray powder diagram of the anhydrous form A.

FIG. 4 shows an X-ray powder diagram of the anhydrous form B.

FIG. 5 shows an X-ray powder diagram of polymorph C.

FIG. 6 shows the thermoanalysis of form C.

DETAILED DESCRIPTION OF THE INVENTION

Within the scope of the present invention it has been found that 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine may take on various polymorphous crystal modifications and that the compound prepared in WO 2004/018468 is present at ambient temperature as a mixture of two enantiotropic polymorphs. The temperature at which the two polymorphs transform into one another is 25±15° C. (see FIGS. 1 and 2).

The pure high temperature form (polymorph A), which can be obtained by heating the mixture to temperatures >40° C., melts at 206±3° C. In the X-ray powder diagram (see FIG. 3) this form shows characteristic reflexes at the following d values: 11.49 Å, 7.60 Å, 7.15 Å, 3.86 Å, 3.54 Å and 3.47 Å (cf. also Table 1 and 2).

Anhydrous polymorph A may be prepared by

(a) refluxing 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine in absolute ethanol and optionally filtering the mixture,
(b) cooling the hot solution or the hot filtrate until crystallisation sets in,
(c) diluting with a solvent such as tert.-butylmethylether,
(d) suction filtering the solvent mixture and
(e) drying the polymorph A at 45° C. in vacuo.

The low temperature form (polymorph B) is obtained by cooling to temperatures <10° C. In the X-ray powder diagram (see FIG. 4) this form shows characteristic reflexes at the following d values: 11.25 Å, 9.32 Å, 7.46 Å, 6.98 Å and 3.77 Å (cf. also Table 3 and 4).

Anhydrous polymorph B may be prepared by

(a) dissolving 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine in absolute ethanol and refluxing and optionally filtering the mixture,
(b) cooling the hot solution or the hot filtrate for crystallisation to a temperature below 10° C.,
(c) diluting with a solvent such as tert.-butylmethylether,
(d) suction filtering the solvent mixture and
(e) drying the polymorph at a temperature below 10° C. in vacuo.

Another polymorph (polymorph C) shows characteristic reflexes in the X-ray powder diagram (see FIG. 5) at the following d values: 12.90 Å, 11.10 Å, 6.44 Å, 3.93 Å and 3.74 Å (cf. also Table 5).

Polymorph C is obtained if

(a) 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine is dissolved in methanol and refluxed and optionally filtered in the presence of activated charcoal,
(b) the methanolic solution is cooled to a temperature of 40-60° C.,
(c) a solvent such as tert.-butylmethylether or diisopropylether is added,
(d) the resulting suspension is first of all cooled slowly to 15-25° C. and then later to 0-5° C.,
(e) the crystals formed are suction filtered and washed again with tert.-butylmethylether or diisopropylether and
(f) the crystals thus obtained are dried at a temperature of 70° C. in the vacuum dryer.

Another polymorph (polymorph D) melts at 150±3° C. This polymorph is obtained if polymorph C is heated to a temperature of 30-100° C. or dried at this temperature.

Finally, there is also polymorph E, which melts at a temperature of 175±3° C. Anhydrous polymorph E is formed if polymorph D is melted. On further heating, polymorph E crystallises out of the melt.

The polymorphs thus obtained may be used in the same way as the mixture of the two polymorphs A and B described in WO 2004/018468 for preparing a pharmaceutical composition which is suitable for treating patients with type I and type II diabetes mellitus, prediabetes or reduced glucose tolerance, with rheumatoid arthritis, obesity, or calcitonin-induced osteoporosis, as well as patients in whom an allograft transplant has been carried out. These medicaments contain in addition to one or more inert carriers at least 0.1% to 0.5%, preferably at least 0.5% to 1.5% and particularly preferably at least 1% to 3% of one of the polymorphs A, B, or C.

The following Examples are intended to illustrate the invention in more detail.

EXAMPLE 1
Crystallisation of Polymorph A

Crude 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine is refluxed with 5 times as much absolute ethanol and the hot solution is filtered clear through activated charcoal. After the filtrate has been cooled to 20° C. and crystallisation has set in, the solution is diluted to double the volume with tert.-butylmethylether. Then the suspension is cooled to 2° C., stirred for 2 hours, suction filtered and dried in the vacuum dryer at 45° C.

FIG. 1 shows the thermoanalysis of the anhydrous form A/B.

Plymorph A melts at 206±3° C. In the DSC diagram another slightly endothermic signal can be seen at approx. 25° C. This is a fully reversible solid-solid phase transition between the two enantiotropic crystal modifications A and B. The form A is the thermodynamically stable modification above this transformation temperature, w| form B is the thermodynamically stable modification below this transformation temperature.

FIG. 2 shows a cyclic DSC diagram, in which the phase transition from −40° C. to 120° C. and vice versa has been run through a total of 3 times. During heating, the phase transition is observed as an endothermic signal and, correspondingly, during cooling it is observed as an exothermic signal. During the first heating cycle the phase transition may also be observed as an endothermic double signal or as a very broad signal while in all the other cycles the signal occurs as a very sharp endothermic or exothermic signal, depending on whether heating or cooling is taking place.

FIG. 3 shows an X-ray powder diagram of the anhydrous form A

TABLE 1

Labelled X-ray reflexes up to 30° 2 Θ with intensities (standardised) for

the anhydrous polymorph A

2 Θ
intensity
d_hkl
labelling
d_exp-calc

[°]
I/I_o[%]
[Å]
h
k
l
[Å]

5.56
1
15.89
1
0
0
−0.008

7.18
32
12.31
0
1
1
0.005

7.62
100
11.59
1
1
0
0.007

8.49
20
10.41
−1
1
1
0.002

9.91
24
8.92
0
0
2
0.003

10.41
18
8.49
0
2
0
0.024

11.18
24
7.91
2
0
0
0.038

11.63
41
7.60
−1
1
2
0.003

12.37
59
7.15
−1
2
1
−0.003

13.19
6
6.71
1
2
1
−0.014

13.45
3
6.58
−2
0
2
0.007

14.05
6
6.30
2
1
1
0.011

14.38
6
6.16
0
2
2
0.003

14.71
10
6.02
−1
2
2
−0.008

15.26
13
5.80
2
2
0
0.001

15.76
10
5.62
−1
1
3
0.008

16.09
1
5.51
1
2
2
−0.010

16.32
1
5.43
2
0
2
0.035

16.69
4
5.31
2
2
1
−0.007

17.03
3
5.20
−1
3
1
0.026

17.63
6
5.03
1
3
1
0.006

18.17
5
4.88
−1
2
3
−0.004

18.78
7
4.72
−1
3
2
−0.014

19.30
1
4.60
−2
3
1
−0.019

19.61
2
4.52
−3
2
1
0.036

19.86
20
4.47
−2
2
3
0.040

20.29
10
4.37
2
0
3
0.019

20.57
4
4.31
0
1
4
0.006

21.12
1
4.20
3
0
2
0.048

21.57
12
4.12
−2
1
4
0.028

22.46
10
3.96
1
4
1
0.035

23.03
35
3.86
4
1
0
0.022

23.39
21
3.80
−1
4
2
0.019

24.08
2
3.69
−3
1
4
−0.006

24.51
1
3.63
−4
0
3
0.036

24.91
10
3.57
−2
4
2
0.003

25.14
39
3.54
3
1
3
0.043

25.69
36
3.47
−3
3
3
0.041

26.68
3
3.34
0
5
1
0.035

26.90
2
3.31
3
4
0
0.027

27.10
2
3.29
0
2
5
0.030

27.42
3
3.25
4
3
0
0.006

28.19
2
3.16
−1
5
2
−0.035

28.54
2
3.12
3
0
4
0.047

28.94
11
3.08
0
4
4
−0.036

29.18
5
3.06
−4
3
3
0.017

29.50
4
3.03
−1
0
6
0.041

30.18
7
2.96
−1
5
3
−0.042

TABLE 2

Lattice metrics of the anhydrous form A

Symmetry:
monocline

spatial group:
P

a:
16.16(2) Å

b:
17.02(1) Å

c:
18.18(2) Å

β:
100.95(6)°

cell volume:
4907(11) Å³

EXAMPLE 2
Crystallisation of Polymorph B

Polymorph B is obtained by cooling form A from Example 1 to temperatures <10° C.

FIG. 4 shows an X-ray powder diagram of the anhydrous form B

TABLE 3

Labelled X-ray reflexes up to 30° 2 Θ with intensities (standardised) for

the anhydrous form B

2 Θ
intensity
d_hkl
labelling
d_exp-calc

[°]
I/I_o[%]
[Å]
h
k
l
[Å]

5.82
3
15.17
1
0
0
−0.007

7.04
33
12.55
0
1
1
0.001

7.82
100
11.3
1
1
0
−0.004

8.84
11
10
−1
1
1
0.001

9.44
40
9.36
1
1
1
0.011

10.62
14
8.32
−1
0
2
0.013

10.79
24
8.19
0
1
2
−0.005

11.82
39
7.48
−1
1
2
−0.003

12.64
53
7
−1
2
1
−0.009

13.07
11
6.77
1
2
1
−0.006

13.24
6
6.68
−2
1
1
0.004

14.04
16
6.3
2
1
1
0.003

15.23
17
5.81
−2
1
2
0.003

15.70
22
5.64
2
2
0
0.016

16.38
2
5.41
0
3
1
−0.010

16.73
6
5.3
2
2
1
0.008

17.67
8
5.02
0
2
3
0.014

18.16
3
4.88
−1
2
3
0.005

18.33
9
4.84
3
1
0
0.016

18.48
10
4.8
−3
1
1
−0.003

18.97
15
4.68
0
0
4
−0.001

19.56
6
4.54
1
3
2
0.013

20.00
17
4.44
2
1
3
0.000

20.42
9
4.35
1
0
4
0.009

20.76
4
4.27
3
0
2
−0.014

20.97
4
4.23
0
4
0
0.010

21.07
5
4.21
1
1
4
−0.009

21.22
12
4.18
0
3
3
0.001

21.40
7
4.15
3
2
1
0.004

21.66
4
4.1
−1
3
3
0.018

21.98
7
4.04
2
2
3
−0.003

22.16
10
4.01
−3
1
3
0.008

22.97
3
3.87
1
2
4
−0.006

23.58
43
3.77
−2
3
3
−0.003

23.78
15
3.74
−2
2
4
−0.004

24.05
6
3.7
4
1
0
−0.002

24.29
8
3.66
−2
4
1
−0.008

24.46
5
3.64
3
3
1
0.018

24.71
7
3.6
0
3
4
0.001

24.96
23
3.56
2
3
3
−0.001

25.45
12
3.5
−2
4
2
−0.010

25.75
35
3.46
4
2
0
0.011

25.99
4
3.43
3
2
3
0.014

26.15
6
3.41
3
3
2
0.010

26.57
12
3.35
−2
3
4
−0.001

26.82
4
3.32
−3
2
4
0.011

27.20
6
3.28
1
2
5
−0.010

27.43
4
3.25
−2
4
3
−0.003

27.60
3
3.23
−2
2
5
−0.005

28.19
4
3.16
3
4
1
0.010

28.40
15
3.14
0
4
4
−0.013

28.64
12
3.11
0
0
6
0.016

29.18
6
3.06
−4
3
2
0.004

29.42
2
3.03
1
4
4
0.002

29.99
10
2.98
0
5
3
−0.008

30.77
3
2.9
−4
3
3
0.018

TABLE 4

Lattice metrics of the anhydrous form B

Symmetry:
monocline

spatial group:
P2₁/c (# 14)

a:
15.23(1) Å

b:
16.94(1) Å

c:
18.79(1) Å

β:
95.6(2)°

cell volume:
4823(3) Å³

EXAMPLE 3
Crystallisation of Polymorph C

Crude 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine (26 kg) is refluxed with 157 l methanol, combined with 1.3 kg of activated charcoal and after 30 minutes' stirring the mixture is filtered and rinsed with 26 l methanol. 122 l of methanol are distilled off from the filtrate, then the residue is cooled to 45-55° C. 52 l of tert.-butylmethylether are added to the residue over 30 minutes. Then the mixture is stirred for another 60 minutes at 45-55° C. Crystallisation takes place within this time. A further 78 l tert. butylmethylether are added to the suspension over 30 minutes and then it is stirred again for a further 60 minutes at 45-55° C. It is diluted to four times the volume. The suspension is slowly cooled to 15-25° C. and stirred overnight at this temperature. After the suspension has been cooled to 0-5° C. the crystals are suction filtered, washed with 2 batches tert.-butylmethylether and dried at 70° C. in the vacuum dryer.

FIG. 5 shows an X-ray powder diagram of polymorph C

TABLE 5

X-ray reflexes up to 30° 2 Θ with intensities (standardised)

for the anhydrous form C

2 Θ
d_hkl
intensity

[°]
[Å]
I/I_o[%]

3.38
26.16
4

6.85
12.90
100

7.18
12.31
11

7.52
11.74
14

7.96
11.10
36

9.80
9.02
3

11.11
7.96
2

11.58
7.64
3

12.30
7.19
5

13.30
6.65
16

13.75
6.44
26

14.38
6.16
17

14.74
6.01
11

14.95
5.92
10

15.63
5.66
6

16.28
5.44
5

17.81
4.98
10

18.33
4.83
6

18.75
4.73
15

20.51
4.33
8

20.77
4.27
8

21.47
4.14
3

21.96
4.05
4

22.59
3.93
26

23.76
3.74
29

24.68
3.60
6

25.01
3.56
7

25.57
3.48
4

25.96
3.43
4

26.93
3.31
18

27.22
3.27
13

27.92
3.19
10

EXAMPLE 4
Crystallisation of Polymorph D

Polymorph D is obtained if polymorph C from Example 3 is heated to a temperature of 30-100° C. or dried at this temperature.

EXAMPLE 5
Crystallisation of Polymorph E

Anhydrous polymorph E is obtained if polymorph D is melted. On further heating, polymorph E crystallises out of the melt.

FIG. 6 shows a thermoanalysis of form C

In the DSC diagram of form C a whole range of signals can be observed. The strongest signal is the melting point of the anhydrous form A at approx. 206° C., which is produced in the DSC experiment. Before the melting point a number of other endothermic and exothermic signals can be observed. Thus, for example, a very broad and weak endothermic signal can be seen between 30 and 100° C., which correlates with the main loss of weight in thermogravimetry (TR). A TG/IR coupling experiment provides the information that only water escapes from the sample in this temperature range.

An X-ray powder diagram taken of a sample maintained at a temperature of 100° C. shows different X-ray reflexes from the starting material, suggesting that form C is a hydrate phase with stoichiometry somewhere in the region of a hemihydrate or monohydrate. The temperature-controlled sample is another anhydrous modification D, which only stable under anhydrous conditions. The D form melts at approx. 150° C. Another anhydrous crystal modification E crystallises from the melt, and when heated further melts at approx. 175° C. Finally, form A crystallises from the melt of form E. Form E is also a metastable crystal modification which occurs only at high temperatures.

Claims

1. Anhydrous polymorph A of the compound 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine, characterised in that it melts at 206±3° C.
2. Polymorph A according to claim 1, characterised in that in the X-ray powder diagram it has inter alia characteristic reflexes at the following d values: 11.49 Å, 7.60 Å, 7.15 Å, 3.86 Å, 3.54 Å and 3.47.
3. Anhydrous polymorph B of the compound 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine, characterised in that at a temperature of 10-40° C. it transforms reversibly into the polymorph A of claim 1.
4. Polymorph B according to claim 3, characterised in that in the X-ray powder diagram it has inter alia characteristic reflexes at the following d values: 11.25 Å, 9.32 Å, 7.46 Å, 6.98 Å and 3.77 Å.
5. Polymorph C of the compound 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine, characterised in that it loses water at a temperature of 30-100° C. and in the DSC diagram it exhibits further thermal effects at approx. 150° C. and 175° C.
6. Polymorph C according to claim 5, characterised in that in the X-ray powder diagram it has inter alia characteristic reflexes at the following d values: 12.90 Å, 11.10 Å, 6.44 Å, 3.93 Å and 3.74 Å.
7. Anhydrous polymorph D of the compound 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine, characterised in that it melts at 150±3° C.
8. Anhydrous polymorph E of the compound 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine, characterised in that it melts at 175±3° C.
9. Method of preparing the polymorph C according to claim 5, characterised in that (a) 1-[(4-methyl-quinazolin-2-yl)methyl]-3-methyl-7-(2-butyn-1-yl)-8-(3-(R)-amino-piperidin-1-yl)-xanthine is refluxed in methanol,(b) the methanolic solution is cooled to a temperature of 40-60° C.,(c) a solvent such as tert.-butylmethylether is added,(d) the resulting suspension is cooled first of all to 15-25° C. and then to 0-5° C.,(e) the crystals are suction filtered and(f) dried in vacuo at a temperature of 70° C.
10. Method according to claim 9, characterised in that after step (a) the hot solution is filtered.
12. A method for the treatment of patients with type I and type II diabetes mellitus, prediabetes or reduced glucose tolerance, rheumatoid arthritis, obesity, or calcitonin-induced osteoporosis, as well as patients in whom an allograft transplant has been carried out, the method comprising the step of administering a pharmaceutical composition comprising at least one of the polymorphs A, B, and C, and one or more inert carriers, diluents, or carriers and diluents.
13. A pharmaceutical composition comprising at least one of the polymorphs A, B, and C, and one or more inert carriers, diluents, or carriers and diluents.

Priority Claims (1)

Number	Date	Country	Kind
06 009 202	May 2006	EP	regional

Information

Publication Number

Date Filed

Date Published

Inventors

CPC

US Classifications

International Classifications

Abstract

Description

Claims

Priority Claims (1)